The present invention relates to vehicle lamp device suitable for use, for example, as a clearance and side marker lamp, which simultaneously provides different lighting functions in the frontward (or rearward) direction as well as in the sideward directions of a vehicle.
Conventionally, there has been employed a clearance and marker lamp which is adapted to be attached to a corner portion of a vehicle body and is arranged as shown in FIG. 1. A lamp 1, using a single bulb, indicates the width of the vehicle and permits recognition of the vehicle from the side. The lamp device 1 is provided with a lamp device body 3 which is mounted adjacent a head lamp 4. The lamp device body 3 is open at the front side and at the outside of the vehicle body, and the front and outside open portions are covered with a clearance lens 5 and a marker lens 6, respectively. The clearance lens 5 is colorless. One end of the clearance lens 5 is inserted into a fitting groove 7 formed in the lamp device body 3 at its open end portion and is fixed thereto through an adhesive or the like. The marker lens 6 is colored amber (or orange). A recursive reflector 10 of well-known construction reflecting external light 9 incident from the side of the vehicle body back in the incident direction and a diffusion lens 12 for diffusing the outward bound light 11 from the bulb 2 are provided on the inner surface of the marker lens 6. The recursive reflector 10 is constituted by a number of recursive reflection elements 13 composed of cubic-cornered protrusions, each having three planes perpendicular to one another. (See Japanese Utility Model Unexamined Publication No. 51-42373.) The diffusion lens 12 is constituted by a number of small convex lenses.
In such a lens 1, light 14 emitted frontwards from the bulb 2 as well as reflected light 15, which is emitted from the bulb 2 toward the center of the vehicle body and which is incident and reflected on an inner surface of a side wall 18 opposed to the outward opening portion of the lamp device body 3, are transmitted outwards through the clearance lens 5. Light 11 directed to the outside is transmitted outwards through the diffusion lens 12 while being diffused by the diffusion lens 12. Light which impinges on the recursive reflection elements 13 as well as the light 11 which impinges on the diffusion lens 12 is partly reflected in such a manner that the reflected light 16 impinges on the inner surface of the side wall 18 so as to be reflected therefrom to pass through the clearance lens 5 towards the outside. Reference numeral 19 designates the vehicle body.
In such a conventional lamp 1, however, there has been a problem in that the reflected light 16, which is emitted from the bulb 2 and reflected n the diffusion lens 12 or the recursive reflection elements 13, is colored amber by the marker lens 6, and when the thus colored light is reflected again from the side wall 18 of the lamp device body 3 and the clearance lens 5 is irradiated with the colored light, the clearance lens 5 appears amber, thereby deteriorating the appearance of the lamp.
Another example of a conventional clearance and marker lamp is arranged as shown in FIG. 2. As in the previously described case, a lamp 21 has a function of indicating the width of the vehicle as well as permitting recognition of the vehicle from the side using a single bulb 22. In the case where the lamp 21 is attached at the front side of the vehicle, the lamp device 21 is provided with a lamp device body 23 provided adjacent to a head lamp 2 at the outside thereof.
The lamp device body has integrally formed therewith a rear wall portion 23A, an inner wall portion 23B and an outer wall portion 23C. The rear wall portion 23A has an inner surface which forms a parabolic reflection surface of revolution 25, the inner wall portion 23B extends frontwards from a vehicle center side edge of the rear wall portion 23A, and the outer wall portion 23C extends from the vehicle outer side edge of the rear wall portion 23A backwards, substantially parallel to the side surface of the vehicle body A. The lamp device body 23 is open at its front side and at its outer surface side, and the open portion is covered with a clearance lens 26, which is colorless. A fixing portion 28 of the clearance lens 26, integrally formed therewith and projecting along the entirety of the circumferential edge of the rear surface of the clearance lens 26, is heat-plate welded on the edge of the opening portion 29 of the lamp device body 23. A substantially rectangular recess portion, namely, a lens attaching portion 30 is formed at a side surface center portion of the clearance lens 26, and a marker lens 27 is fitted and ultrasonically welded to the lens attaching portion 30. The marker lens 27 is colored amber (or orange) and provided with a recursive reflection portion 31 and a marker portion 32. The recursive reflection portion 31 is constituted by a number of triangular-pyramid recursive reflection elements provided on a portion of the rear surface of the marker lens 27 projecting therefrom to recursively reflect external light L.sub.1 incident on the marker lens 27 substantially perpendicularly thereto from the side of the vehicle body. Thus, the reflected light is returned in the same direction as the incident direction. The marker portion 32 is constituted by a plurality of rod-like diffusive convex lenses each of which has semicircular cross-section, which extend elongatedly vertically (in the direction perpendicular to the plane of the drawing), and which are arranged side by side in the longitudinal direction of the vehicle body. The marker portion 32 has an area smaller than that of the recursive reflector portion 31 and is surrounded by the reflector portion 31. The bulb 22 is inserted into the lamp device body 33 through a bulb-insertion hole 34 formed in the rear wall portion 23A of the lamp device body 23 with a filament 22a of the bulb 22 located at a focal point 0 of the reflective parabolic surface of revolution 25.
Reference numeral 35 designates a socket plug, and 36 designates an end rubber member for sealing between the vehicle body A and the outer wall portion 23C of the lamp device body 23.
In the thus-arranged lamp 21, of the light emitted by the bulb 22, direct rays of light L.sub.3 directed toward the front of the vehicle body, reflection light L.sub.4 directly incident on the reflective parabolic surface of revolution 25 an reflected frontwards therefrom parallel to an optical axis 37, and reflection light L.sub.5 directly incident on the inner surface of the inner wall 23B and reflected therefrom slantingly frontwards pass through the clearance lens 26 at its front portion to thereby indicate the vehicle width. On the other hand, a part of thelight L.sub.2 directed to the outer side of the vehicle body exits to the outside after being diffused by the marker portion 32 to thereby make it possible to recognize the vehicle body from the side direction of the vehicle. The remaining part of the light L.sub.2 is incident on the marker portion 32 or a rear surface 30a of the lens attaching portion 30 and reflected inward therefrom.
Light L.sub.1, which is a part of the light externally incident from the side direction of the vehicle body, is recursively reflected by the recursive reflector portion 21 in the same direction as the incident direction, and light L.sub.6, which forms the other part of the externally incident light, is incident into the lamp 21 through the marker portion 32 and the lens attaching portion 30, and then reflected again on the inner surface of the inner wall portion 23B so as to pass through the front portion of the clearance lens 26 while lighting that portion.
However, similar to the first-described case, such a conventional lamp 21 has a problem in that the light L.sub.6 incident into the lamp 21 through the marker lens 27 and the lens attaching portion 30 from the side direction of the vehicle body as described above is colored in the color of the marker lens 27 (amber), so that when irradiated with the light L.sub.6 reflected on the inner surface of the inner wall portion 23B, the clearance lens 26, which should appear white, looks amber when viewed from the front thereof, add thus the appearance of the clearance lens 26 is poor. This applies to a part o the light L.sub.2 directed from the lamp to the outside of the vehicle body. This is because light L.sub.7, which is emitted from the bulb 22 toward the outside of the vehicle body, transmitted through the lens attaching portion 30, and reflected by the recursive reflector portion 31 or the marker portion 32, is incident on the inner surface of the inner wall portion 23B and reflected again therefrom. The reflected light L.sub.7 is transmitted through the front portion of the clearance lens 26 while illuminating that portion.